Funny you should ask while I'm listening to Elvis, Harpy. Here's a quote from David Ewen's American Popular Songs: From the Revolutionary War to the Present (1966, Random House)

Hound Dog, words and music by Jerry Leiber and Mike Stoller (1956). Introduced by Willie Mae Thornton in 1953, but published in 1956 and popularized that year by Elvis Presley in an RCA Victor recording that sold over two million disks.

-Joe Offer, in respectful disagreement with 'Spaw-